Utility distribution systems or networks, such as natural gas distribution systems, are often comprised of various pipes made of high-strength, rugged, plastic materials such as polyethylene. These various-sized plastic pipes are connected to form such a distribution network. The connections or junctions used to connect such pipes may be provided using any number of known or available techniques or arrangements. For example, a saddle tap type device may be used to connect smaller pipes to the side of a larger plastic pipe. Frequently, a saddle tap device is employed that is attached to the outer surface of a main plastic pipe and made to tap into the main plastic pipe so as to communicate the flow of fluid, such as natural gas, from within the main plastic pipe to a tributary line or pipe extending therefrom. Often such connections or junctions, including saddle taps, develop leaks that require repair.
The repair of such connections or junctions is cumbersome, time consuming, and expensive. In many cases, a large excavation is necessary to make sufficient room for clamping the main plastic pipe on both sides of the leak. Clamping is necessary to prevent the natural gas from leaking during the repair. A bypass is then constructed to allow for the continued flow of natural gas through the main plastic pipe. The squeezing is accomplished by placing a device adjacent to both sides of the connection or saddle tap that squeezes the plastic pipe to prevent the flow of natural gas therethrough.
The squeezing process, however, is often only allowed when the plastic pipe diameter is six inches or less. In many instances, the squeezing process is not practicable. Squeezing pipe with a diameter greater than six inches is normally considered ineffective at controlling the leaking natural gas, and may cause damage or stress at the pinch point of the plastic pipe. Such weakening of the plastic pipe may create a safety hazard after multiple squeezings.
Since squeezing the pipe may weaken the pipe, the squeeze points must be marked for future reference thereby leaving the marked areas unusable for future squeezing due to safety concerns.
Additional repair considerations of plastic pipe connections or junctions are well known. These include, for example, cutting out the damaged connections or junctions, removing burrs and shaving the repaired portions of the pipes, preparing pipe ends, attaching new pipes with collars, installing alignment clamps or jigs, opening squeezers to purge air from the pipes, opening both squeezers, rounding squeeze points, marking squeeze points, and fusing a bypass to the pipe.
Thus, it is readily apparent that the current method for repairing leaks in plastic pipes fitted with saddle taps for transporting natural gas under pressure is a lengthy and time consuming process that suffers from various disadvantages.